Endogenous MPTP-Like Amines in the Brain: Isoquinolines

The discovery of N -methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) as a parkinsonism-producing neurotoxin (Davis et al., 1979; Langston et al., 1983) has greatly contributed to the pathogenesis of Parkinson’s disease. Efforts have been made to find MPTP-like neurotoxins in the brain of parkinsonian patients. MPTP is a precursor neurotoxin, and the oxidized form, by monoamine oxidase type B, N -methyl-4-phenylpyridinium ion (MPP + ), is the active neurotoxin (Chiba et al., 1984). It is assumed, therefore, that if any hypothetical MPTP-like neurotoxins exist in the parkinsonian brain they might be oxidized by monoamine oxidase to active neurotoxins. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.